This invention relates to a plaster backing panel for a ventilated curtain wall system, comprising essentially a rectangular light-weight wood-fiber panel which is mounted on a framework attached to a vertical building wall so as to leave an air space of predetermined size for ventilation.
Plaster backing panels of the above type are made of a light-weight wood-fiber panel as per DIN Specification 1101 and are generally available in dimensions of 200 cm.times.50 cm, and a thickness of 8 mm. They have crosswise indentations which provide a certain rigidity. Lengthwise, however, the plaster backing panels have only low inherent rigidity. Thus, a framework is needed for mounting such panels, which consists of an inner wood lathing adjoining the building wall and an outer wood lathing placed perpendicularly on top of the panel. The wood slats which make up the outer wood lathing are placed relatively close together, i.e. at intervals of 40-50 cm. The plaster backing panels are placed flush against each other and are secured to the outer lathing with screw nails. In order to obtain better anchoring of the subsequent plaster layer, a wire netting with a mesh size 25.times.25 mm and 1 mm wire thickness is hung on the outside for bridging the joints between individual plaster backing panels, in order to avoid cracks in the plaster, and for increasing the rigidity of the plaster layer, since the plaster backing panel itself has only a relatively limited inherent rigidity. For this reason it is also necessary to apply a three-layer plastering system, starting with a sprayed cement layer which encases the wire netting and which must cure and dry before the first plaster coat can be applied. The final coat is then applied over the first coat. This familiar plaster backing panel is thus relatively labor intensive at the construction site. Specifically, a relatively tight outer lathing must be attached on the inner lathing, and after mounting the plaster backing panels, the close-meshed netting still has to be put on for plaster reinforcement. Applying a three-layer plaster system is also labor intensive.